J. Org. C h e m . , Vol. 41, No. 2,1976 319
0-Phenethylamine and Tetrahydroisoquinoline Alkaloids 6.60 ( 8 , 1 H), 6.81 (d, J = 8 Hz, 2 H), 7.06 (d, J = 8 Hz, 2 H); mass spectrum mle (re1 intensity) 333 (M+
-
book of Organic Medicinal and Pharmaceutical Chemistry", 6th ed, Lippincott, Philadelphia, Pa., 1971,pp 473-494. (19)W. H. Vogel, B. D. Evans, E. M. Bonnem, J. F. Fischer, and J. L. McLaughiin, Psychopharmacologia,30, 145 (1973). (20)G.0.Ferguson and W. J. Keller, J. Pharm. Sci., 64,1431 (1975). (21)Plants were purchased from Abbey Garden, Reseda, Calif., and from Dickinson's Cactus, San Saba. Texas. Identifications were confirmed by Mr. Charles Glass, who is editor of the Cactus and Succulent Journal. Photos of the plants are available and living specimens are being maintained in our greenhouse. (22)J. S.Buck, J. Am. Chem. SOC.,56, 1769 (1934). (23)Reference (-)-normacromerine hydrochloride was isolated from the cactus Coryphantha marcomeris var. runyonii. (24)W. J. Kelier, Ph.D. Thesis, University of Washington, 1972,pp 43-45. (25)S.V. Kessar, A. L. Rampal, K. Kumar, and R. R. Jogi, Indian J. Chem., 2, 240 (1964).
Protonated Cyclopropane Intermediates from the Deamination of 3-Methyl-2-aminobutane Allen G. Meek, Zack Z. Martin, Howard A. Nadworny, and Marc S. Silver* Department of Chemistry, Amherst College, Amherst, Massachusetts 01002 Received August 20,1975 The formation of 1,2-dimethylcyclopropanesin the aqueous deamination of 3-methyl-2-aminobutane suggests that the 3-methyl group of the amine plays a role in the reaction. The extent of this role has now been established. Deamination of optically active amine provides trans- 1,2-dimethylcyclopropane with 57 f 2% net inversion and 3-methyl-2-butanol with a remarkable 37 f 3% net retention of configuration. Study of the products obtained by deamination of 3-methyl-2-aminobutane-1,1,1,3-d~ proves that 37 f 4% of the 3-methyl-2-butanol formed but essentially none of the 2-methyl-2-butanol has undergone 1,2-methyl rearrangement. A scheme postulating the intervention in the deamination reactions of corner-protonated (methylene carbon) cis- and trans- 1,2-dimethylcyclopropane intermediates adequately rationalizes all the observations. This mechanism cannot be distinguished from one implicating rapidly equilibrating edge-protonated cyclopropane intermediates, Several carbonium ion reactions apparently generate's2
the protonated cyclopropane cation, c-C3H7+. For example, postulation that deamination of 1-aminopropane-1- 14C produces a trace of c - C ~ H ~ provides + a simple explanation for t h e fact that t h e C3& fraction obtained contains 10% cyclopropane and that positions 2 a n d 3 of t h e 1-propanol formed each contain 2% of t h e I4C label. Whether c-C3H7+ is best represented as edge- or corner-protonated remains undecided.*J
Protonated cyclopropane intermediates seemingly are less important in t h e deamination of higher alkylamines. The hydrocarbon fraction obtained from deamination of .n-, sec-, or isobutylamine, 1-aminopentane, %aminopentane, isopentylamine, or 2-methyl-1-aminobutane contained only 1-5% of t h e pertinent alkylcyclopropane deriva t i v e s . * ~Likewise ~ deamination of suitably deuterium-labeled n-, sec-, or isobutylamine afforded butanols and methylcyclopropane which revealed almost none of t h e
